Dental plugger



2 Sheets-Sheet 1..

(Model.)

B. FITTS..

DENTAL PLUGGBR.

Patented Oct. 17, 1882.

New@

'I IIIIIIIIIIIIAI NTE EN New@ UNITED STATES PATENT QEETCE.

BENAIAH FITTS, OF IVORCESTER, MASSACHUSETTS.

DENTAL PLUGGER.

SPECIFICATION forming part of Letters Patent No. 265,950, dated October 1'7, 1882,

Application filed June 16, 1882.

Tocll whom it may concern Be it known that I, BENAIAH FITTS, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Mas- .sach usetts, haveinvented certain new and useful Improvements in Dental Pluggers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accom pan yin g d rawings, and to letters or figures of reference marked thereon, which form a part of this specification. v

This invention relates to dental pluggingmachines; anditconsists principally in a valve having reciprocating and partial rotary motion, in combination with its case, a hammer operated by air passing through said valve, a plu gger-point operated by said hammer, a cylinder inclosing said hammer and provided with an opening, and an adjustable device for partly closing or uncovering said opening and thereby determining the rapidity ot' the hammer-strokes.

It also consists in additional improvements in construction and combination of parts, as hereinafter set forth and claimed.

The drawings accompanying this specification represent, in Figures l and 2, longitudinal sections of a dental plugger containing my improvements, while Fig. 3 is a longitudinal section of the valve-case and valve and parts. Fig. 4 is an under side view, and Fig. 5 a plan, of the valve-case. Figs. 6, 7, S, 9, 10, 11, and 1,2 are cross-sections through the valve-and handle. Figs. 13 and 14 are crosssections through the cylinder. Fig. 15 is a plan ofthe valve. Figs. 16, 17, and 18 are views showing the manner of connecting the valve with the mechanism by which its axial vibrations are effected.

A in such drawings represents a hollow cylinder, whose bore a is of uniform diameter, and I have shown this-cylinder in the present instance as curved, or describing the arc of a circle longitudinally, in lieu of being straight, the better to adapt it to the various changes in position required for dental uses.

In ordernto have a clear understanding of the construction and operation of this engine,

(Model.)

I have represented the outlet end of the cylder A--that is, the end at which the air operates to drive the hammer ot' the plugger-at l, and the inlet end, by which the air enters the cylinder, at 2. The piston A containedin the cylinder A, and which constitutes the hammer of the plugger, is a plain round bolt in the form longitudinally of an arc ot' a circle or curve, and corresponds to the bore of the cylinder. The ends of this piston hare preferably fiat radii of the circle of which the arc is part. The inlet end 2 ot` the cylinder is closed by a head, B, which is pierced by alive supply-port, b, while the exit-port at the opposite end, 1, of the cylinder is shown at c as occupied by the head of the plugger-point, to be hereinafter described.

The valve-chamber is thebore C of a straight circular tube, D, contained within an outer shell or case, E, which constitutes the handle of the plugger, and is adapt-ed to closely surround such tube, this case E having a supplyport, F, at one end, through which air under pressure inds its way to the valve-chamber by a channel or roadway formed in one end ofthe circumference ofthe tube D,-as shown at d in Figs. 1, 5, 6, 7, and 8 of the drawings. The inner end of this channel d terminates in a radial passageV or port, e, (see Figs. 1 and 5,)

this passagef being of larger diameter than the greatest diameter of the valve. Iform in the opposite end of the outer circumference of the tube D a second longitudinal channel or roadway, G, (see Figs. 1, 5, and 7,) the inner end of which terminates in a radial port or passage, g, which is a com paniou to the port f, and in line.with it lengthwise ofthe tube, and is sepa-ra ted from said portf by a narrow integral ledge or unbroken portion, i, of the tube D, Figs. l and 13, such ledge being practically midway of the ends of the said tube, while the port G is continued into an annular peripheral channel, g4, formed in the wall of the bore of the tube D. The channel lis continued beneath or behind the head B of the cylinder,-

IOO

iiir

thence extends through the cylinderI and makes exit int-o lthe bore (tof the latter at its extreme opposite end by a port, g. In addition to the channels G d and ports e g, I form in the circumference of the tube l), and upon the same end as the passage G, a third parallellongitudinal passage or roadway, Z, Figs. 2 and 5, extending from the front end of the tube rearward to and communicating with a radial port, e', formed in the wall of the tube, this port c making part of an annular passage or channel, m, in the inner circumf'erence of the tube I) parallel with the channelsfand g4. In addition to the annular channels f, g4, and on, I form in the inner periphery ofthe tube D two other annular channels, n 0, Figs. 1 and 2, parallel with the channelsf, g4, and m, and of like size, the purposes of these two last channels being hereinafter explained.

To avoid confusion l shall first describe the construction and operation of the valve in relation to its functions in governing the ports which control the admission of air to the cylinder and the exhaust therefrom, afterward describing the motions of the valve as impelled by the slide-bar before named.

The valve, as shown atH in the drawings, (sce Fig. 15,) is a straight cylindrical bolt, adapted in its greatest diameter to closely ll the valvechamber, and being formed with two peripheral annular channels, jj, separated by a narrow peripheral ledge, p, these channels j j, Figs. 1, 2, and 15, constituting in conjunction alternately passage-ways for live air and governing the supply of the same to the cylinder A, as well as to the valve-chamber c. These channelsjj are of such width as to embrace the two central pairs of peripheral channels in the bore of the valve-chamber with the intervening ledge, as shown in Figs. 1 and 2 of the drawings, and constitute passages by which air may pass from one to the other of such pairs of channels.

I in the drawings, Figs. 1, 2, and 11, represents a curved bar contained and playing longitudinally within achamber, J, formed in the body of the cylinder A, below its bore a, and parallel with the channel l, the length of the bar being slightly less than that of the bore of the cylinder, and having upon each end a' spur, r or s, which extends into the said bore, and so as to intercept the piston as the latter completes its motion in either direction. rlhe inner end of the slide-bar I is loosely attached in a suitable manner to the outer end ot' a cylindrical head or bolt, K, (see Figs. 1 and 16,) which is contained loosely within a socket or chamber, L, formed in the base of the cylinder A below its head B, the inner end, t, ofthe head or bolt K extending into the valve-chamber c, and being formed with an axial'socket, u, polygonal or square in crossscction, which loosely receives an axial horn or spur, c, from the adjacent end of the valve, this spur e being adapted to slide longitudinally, but not rotate within the socket u.

Suppose the valve to be in its extreme position to the right, as shown in Figs. 1 and 2 ot the drawings, and the piston A at the corresponding end of the cylinder A, in which case the valve-channel j is in communication with the inlet supply-channel d and port e, and the peripheral channels n g4 of the valve-chamber, while the channel j of the valve is in cornmunication with the passage Z and porte', the two pairs m o andfg4 of channels being divided by the central rib orledge), of the valve closely tillingthe bore ofthe valve-chamber. Air under pressure enters the valve-chamber c by way of the inlet F, flows into and through the passage d and port c into the channel] of the valve, (see Fig. 1 ofthe drawings) thence pours from such channel j, escapes by way of port g into channel G, and from the latter enters the cylinder A by the port b and impels the piston in the direction of the arrow 1 until such piston reaches the opposite end of the cylinder and delivers its blow upon the pluggerpoint, which is shown in Figs. 1 and 2 of the drawings, at l, as of the form and adaptation to be hereinafter explained. As the piston completes its traverse and imparts the blow to the pluggerpoint, a portion of the air in front ofsuoh piston, which may be termed the exhaust, es'- capes from the cylinder A through the port g into and through the channel l and port e', into the channel j of the valve, thence into the peripheral channels m o of the valve-chamber, and exhausts or escapes from the instrument by exit-port w, leading from the channel o, as shown in Fig. 7 of the drawings. As the piston completes its stroke last named and imparts a blow to the plugger-point, such piston, immediately prior to delivering this bio w, abuts against the s'p'nr r of the slide-bar I, and carries the latter with it until its traverse is completed, thereby rocking the head or bolt Ii, and through the latter the valve'H, and shifting the latter to the other set of ports, by which its motion is reversed, as hereinafter explained. The valve H now moves longitudinally-in the direction of its arrow 2 until its channelj embraces the two outermost channels, u g4, of the valve-chamber, and its channel j the channels f m of such valve-chamber, the channel o being closed by the solid portion ofthe valve, so far as connections between this channel o and the valve-chamberc is concerned, while the central rib or ledge,p, of the valve is during the travel of such valve shifted from between the portsfm to a point between the -ports f and g, so as to shut oft' communication between the ports e and g. Live air now iows through the passage d and port e into the channely' of the valve, thence into the channels f and m of the valve-chamber'c, and makes exit from the latter by the port e into the passage l, thence through the latter by way of the port g" into the cylinder A, and drives the piston in the reverse direction on its return-stroke, as shown by arrow 3.

The passage l, which, on the direct stroke of` IOO IIO

first was the live-inlet) and port g, into the` channel j of the valve and channels a g4 of the valve-chamber, and exhausts from the instrument by way of a port, y, leading from said channel a, as seen in Fig. 3 of the drawings 1o and dotted lines in Figs. l and 2. As the piston or hammer Al completes its return-stroke last named it abuts against the slide-bar I, and carries the latter with it until it completes its stroke, thereby rocking the head or bolt K and i5 valve H in the opposite direction and shifting such valve with respect to its supply-ports.

l will now describe the arrangement ofparts which govern the longitudinal traverse ofthe valve.

2o In the under side of the outer or front end,

t3, of the tube or valve-case D, I create two radial parts, ct b', (see Figs. 4 and 6,) which communicate alternately with a longitudinal channel, c', formed in the periphery of the outer end -of the valve, (see Figs. 6 and 15,) the extentof axial rocking motion ofthe valve at the hands of the slide-bar I and bolt or head K being sufficient to shift the port cfrom one to the other of the ports ct b. When the valve is in its extreme inward position, as shown in Figs. l and 2, the inner boundary of the channel c' is covered by the solid portion of the valve-case. When the valve is in its opposite or outward position the inner boundary ofthe said channel c coincides with either the port a or b', as the case maybe. The port b communicates with the outer end of a channel, d2, created Vin the circumference of the valve-case D, this channel cl2 being ar- 40 ranged obliquely to the axis of the said case D to such an extent that its rear inner termination is in axial alignment with the port a', (see Fig. 4,) and is continued into a radial port, e2, Figs. 3, 4, and 9, formed by the valve case D and communicating with the rear end of the valve-chamber c when the valve is 'in its extreme outermost position, as shown in Fig. 3. Furthermore, I form through the valvecase D, at its rear end and on a peripheral line with the port e2, a radial port, f2, (see Figs. 2, 4, and 8,) which, like the said port e2, enters the rear end of the valve-chamber, and this port f2 communicates by a passage, g2, formed longitudinally in the periphery of the valvecase D, Figs. 2 and 4, with a radial port, h2, extending through the valve-case and opening communication between the port e2 and the channel o of the valve-chamber, Figs. 2, 4, and 7. The ports f2 h2, channel g2, and port b are 6o in alignment with the axis ofthe valve H and valve-case D. Continuing this portion of the instrument, I form a radial port, t2, Figs. 2, 4,

- and G, in the valve-case D, which enters the valvechamber at a point to communicate with the peripheral channel a ofsuch chamber, this port t2 and the port a being connected by a short channehj?, as shown in Figs. 2 and 4.

I also form a radial port, k2, in the valve-case D, which enters the peripheral channel f of the valve-chamber and intercepts the long oblique channel cl2. (See Figs. 2, 3, and 4.)

Finally, I form in the periphery ofthe valve El,

at its rear or inner end and in axial alignment with the channel c', before named, a

short longitudinal channel, Z2, (see Figs. 2, S, and 15,) the length ot' which is such that when the valve is at its extreme rearward position,

as shown in Figs.1 and 2 ofthe drawings, the

inner termination of this channel coincides alternately with the ports c2 f2, and when the valve is in its extreme outward position, as

shown in Fig. 3, the channel lZ is covered by the solid portion of the valve-case.

While the valve is being driven to its extreme rearward position, (to the right in the drawings,) as shown in Figs. l and 2, live air is admitted into the valve-chamber in frontot' the valve from the space surrounding the channel j of such valve by way of the port k2, channel d2, and port b', and as the valve reaches its extreme rearward position the piston or hammer encounters the spurr of the slide-bar I, and, by moving such bar, rocks the valve (by means ofthe intermediate head or bolt K,) to such an extent that its channel c is brought into coincidence with the ports ct and t2 and channel jz, while its channel l2 is brought in communication with the ports e2, k2, and b and channel d2. The live air now enters the valvechamber surrounding the channel j ot' the valve through the channel d2 by way of port k2, flows through port c2 and channel Z2 into the rear end oi' the valve-chamber, (see Fig. 3,)and impels the valve in the direction of its arrow 2. As before stated, live air now passes from valve-chamber c to the cylinder by way of the portg and passage Gr b, and the hammer A is driven in direction of arrow l, as tirst stated. As the hammer A completes its stroke it moves the bar I and rocks the valve in the opposite direction, thereby bringing the valve-chamber c into communication with the ports b', e2, and k2, while the channel Z2 of such valve is covered and idle. Air now enters the front end of the valve-chamber by way ot' the ports k2 and b and passage c', and drives the piston rearward until'it brings up at the opposite end ot' its chamber.

It is not essential that the cylinder A should be curved, as explained. It may be straight and in axial alignment with the handle E, and in this case a plain slide-valve may be employed in lieu ot' a cylindrical one having the compound motion explained, or the entire body ofthe instrument, including the handle, with some modications ot' the valve, may be upon a curve in lieu of the handle being straight.

I prefer that the position of the axis of the plugger-point shall be a tangent to the curve ofthe bore of the cylinder, as shown in Figs. l and 2 of the drawings, in order that the blows ofthe hammer upon the head of such ICO the repetitive blows of the hammer shall be i comparatively slow, while the blow struck is a quick and powerful one, I have added to my instrument means for permitting the hammer to return as slowly as maybe desired, while it is driven forward with great rapidity and momentum. To effect' this I have shown in the iresent'instance a sleeve a3 surrounding and adapted to slide upon'the cylinder A, and operating to open or close to any extent an opening, b3, in such cylinder. The greater the area of the aperture b3 the less the power exerted upon the hammer A in its return-stroke, and vice versa.

I claiml. A valve having reciprocating and partial rotary motion, in combination with its case, a hammer operated by air passing through said valve, a plugger-point operated by said hammer, a cylinder inclosing said hammer and provided with an opening, and an adjustable device for partly closing or uncovering said opening and thereby determining the rapidity of the ham merstrokes, substantially as set forth.

2. In combination with the tubular cylinder A, piston-hammer A', and valve H, the head or bolt K, connected with one end of the slidebar I, the latter having` spurs upon each end protruding into the cylinder to intercept the hammer, substantially as stated.

3. The passage l, in combination with the cylinder A, piston-hammer A', handle E, and valve H with the various ports and passages, as hereinbefore described, whereby the said passage becomes during the direct stroke of the hammer a vent or exhaust. to the cylinder, and on the return-stroke of the hammer a direct live-port, substantially as before described.

4. In Combination with the cylinder and its with such cylinder and with the valve-cham.

ber, as explained, whereby air admitted to the cylinder direct by way of the port g and passage G b exhausts by way of the passage Zand .port e.

In testimony whereof I affix my signature in presence of two witnesses.

BENAIAH FITTS. Witnesses:

H. E. LODGE, F. CURTIS.

`piston-hammer and vent or exhaust-passage, a device for governing the area or capacity of such exhaust, for purpose explained. 

